Band saws usually have a frame on which a workpiece can be supported or clamped. The saw band can be fed against the workpiece, for example by being retained in a saw band holder which is movable with respect to the workpiece. Usually, the workpiece is positioned on a horizontal table and the saw band is operating essentially horizontally. The saw band is an endless belt, with cutting teeth thereon, running about operating wheels, at least one of which may be driven. The saw band, together with the deflection wheels about which the band or belt runs, is carried in a band holder. The band holder can be pivotably secured to the machine frame, so that the band can be pivoted out of engagement from the workpiece, and then, downwardly, into engagement with the workpiece, the saw band or belt cutting through the workpiece as the saw band is fed thereagainst. In another arrangement, the saw band holder is slidable on a pair of posts, the saw band holder being guided with respect to the machine table, and hence the workpiece, in a parallel movement, so that the saw band cuts essentially across the workpiece with a cut which is of uniform length from beginning to end, rather than changing as in the pivoting type machine.
All such power band saws have the common feature that the cutting tool is a belt which, as the workpiece is about to be cut, has a cutting edge which extends essentially parallel to the workpiece support. When workpieces are sawed in this manner, the cross section of the cut will be essentially parallel to the machine table; or, at least a portion of the workpiece, for example if it has a relief will be parallel to the workpiece. As the cut proceeds towards its final cut-through point, the saw band suddenly is released from the cross section of the workpiece material. As the saw band cuts, it has the tendency to slightly deflect in a curve counter the feed direction, due to the cutting forces which are required, even though the saw band may be tightly stretched. This stress on the saw band is suddenly released as the workpiece is completely cut through. At that sudden release, the saw band is dynamically stressed, which leads to formation of burrs or, if the workpiece is fibrous, for example of wood, splintering at the cut edge.
The bowing-through of the saw blade, during the cut, as well as sudden release of the bowing stress upon complete severing of the workpiece, can be ameliorated by not feeding the saw band essentially parallel to the work table but, rather, at a slight inclination. Consequently, the cross section of the material which is cut as the complete severing point is reached decreases continuously, so that the stress placed on the saw band decreases before the workpiece is completely severed. This arrangement is particularly suitable in miter saws or the like. In such saws, the inclination of the saw band is so arranged that the inclination angle, with respect to the workpiece support or plane, is counter the cutting direction of the saw band. As a consequence, the complete cut-through of the workpiece causes a burr or splinter to occur only at the final severing position, and directing the final burr or splinters in the direction of the remainder of the cut which is to be made in the workpiece material.